1. Field of the Invention
The present invention relates to a mount for attaching a radio antenna to the roof or other body panel of a vehicle.
2. Description of the Prior Art
Many different types of mobile antenna mounts are available and have been proposed, most of which are complex, difficult to install, and require making a large hold in the automobile roof or other body panel to which the antenna is to be attached. For example, a common size of lead-in electrical conductor cable used in connection with mobile radio antennas is a so-called RG-58A/U type coaxial sheathed cable having an insulated outer sheath, an outer conductor cable within the sheath, an insulated inner sheath, and an inner conductor cable within the inner sheath. Such a conductor cable has a nominal outer diameter of approximately three-sixteenths inch. Many available mobile antenna mounts for accomodating a lead-in cable of this size require drilling a 3/4 inch hole in the body panel of the vehicle for insertion of a flange-type clamping portion of the antenna mount and clamping the mount in blind fashion to the underside of the panel. A hole of this size is not only difficult to seal against water, but is also difficult to conceal if the antenna mount is ever removed.
One available type of mobile antenna mount not requiring such a large hole is one having a snap-in type blind anchor. However, such snap-in anchors are not entirely satisfactory because once installed, they are difficult to remove. Also, the effective clamping surface of snap-in anchors must necessarily be small because of the inherent nature of this type of anchor. This results in a relatively uncertain connection which can be inadvertently released if the installation hole should later become enlarged through the effects of vibration or other factors.
Prior mounts of the flange type rely on some sort of clamping flange for gripping the underside of the vehicle body panel. The flange- or shoulder-bearing element typically is carried at the lower end of a threaded stud. The stud is screwed into the antenna base after insertion of the flange through the installation hole to clamp the flange against the underside and the antenna base against the upper side of the panel. The clamping flanges of prior known mounts are symmetrically arranged with respect to the axis of the threaded stud to which it is attached, thereby requiring a hole in the roof having a diameter slightly in excess of the sum of the outer diameter of the stud and one-half the total length of the flange extension beyond the stud.
Examples of various common prior flange and snap-in type mounts as described are shown in a four-page sales brochure entitled "Larsen 150 MHz Mobile Gain Antennas" (Form 73150) published by Larsen Electronics, Inc., of Vancouver, Wash.
Other typical prior mounts are shown in U.S. Pat. Nos. 3,624,662; 3,545,148; 3,492,769; 3,444,313; 3,267,476; 3,076,936; 2,946,842; and 2,786,884, all requiring relatively large-diameter mounting holes in the vehicle roof or other body panel because of their symmetrical clamping structures.
From the foregoing the need for an improved antenna mount of simplified weatherproof construction, providing easy installation and removal and requiring only a small mounting hole for the clamp assembly of such mount, will be apparent.